The goals of phase 1 of this project are to develop a set of tasks in which both behavior and cortical event-related potentials (ERPs) are recorded to assess age-related changes in specific aspects of perceptual, congnitive, and motor functioning. Normal controls aged 20-30 (N equals 16) and subjects over 60 years of age with various degrees of behavioral impairment (N equals 32) will be given a set of tasks designed to assess both the speed and accuracy of specific perceptual, cognitive, and motor functions associated with the processing of verbal and non-verbal materials; behavior and ERPs recorded in these tasks will allow a specification of differences in CNS functioning between and within these groups. The aim of this phase of the project is to assemble a series of tests, sensitive to behavioral impairments associated with age, which can then be applied to evaluate the effectiveness of substances believed to enhance cognitive abilities in the elderly.